1. Field of the Invention
This invention is in the field of sheet support apparatus, and more particularly in the field of such apparatus for mounting sheet materials to be displayed.
2. Description of the Prior Art
Many types of mounting an apparatus for displaying sheet material have been devised. One type that is known is a rigid frameformed from wall members integrally connected and formed to provide a cavity into which a spring can be inserted. Sheet material such as paper or cardboard are inserted into the cavity and are anchored therein by the spring.
It has heretofore been typical with such frame members to position the wall members in such a way as to only provide a very small opening at the point where sheet material is inserted into the cavity. This was done to retain the spring element within the cavity where it was so placed under compression.
While such supports do serve the main purpose, they have several inherent drawbacks. Since one wall member has to be forced into close relationship to another, the typical entrusion manufacturing process is encumbered by the addition of a cold rolling step. This is necessary since the frame cannot be directly exturded with wall members having the required angle where they join. Besides being time consuming and expensive, the cold rolling step also creates a point of weakness where the wall member which is positioned by cord rolling joins to the other wall member. Additionally, since the opening in the frame leading to this cavity is very small, it has been heretofore required that the spring anchoring means be inserted only from the end of the frame and not from the side or cavity opening. This was a particular problem where the frame extended for more than very short distances.